Post-self-assembly cross-linking to integrate molecular nanofibers with copolymers in oscillatory hydrogels

We study the use of post-self-assembly cross-linking to combine molecular nanofibers of hydrogelators with copolymers to generate oscillatory materials using the Belousov-Zhabotinsky reaction. The formation of nanofibers from designed hydrogelators provides multiple polymerizable sites for copolymerizing with N-isopropylacrylamide and for attaching a catalytic ruthenium bipyridine complex on the copolymer. The combination of supramolecular self-assembly with copolymerization offers a versatile and facile approach for generating soft materials that have large pores in the gel network and robust mechanical integrity. These larger pores facilitate the diffusion of the reactants and accelerate the chemical oscillation by about a factor of 4 relative to a poly(NIPAAm-Ru) gel that contains no molecular nanofibers.